@Article{PadilhaVitoPáduFuck:2016:DeMaSi,
               author = "Padilha, Antonio Lopes and Vitorello, {\'{\I}}caro and 
                         P{\'a}dua, Marcelo Banik de and Fuck, Reinhardt Adolfo",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and {Universidade de Bras{\'{\i}}lia 
                         (UnB)}",
                title = "Deep magnetotelluric signatures of the early Neoproterozoic 
                         Cariris Velhos tectonic event within the Transversal sub-province 
                         of the Borborema Province, NE Brazil",
              journal = "Precambrian Research",
                 year = "2016",
               volume = "275",
                pages = "70--83",
                month = "Apr.",
             keywords = "Northeast Brazil, Borborema Province, Magnetotellurics, Subduction 
                         zone, Neoproterozoic, Cariris Velhos Orogeny.",
             abstract = "The Borborema structural province, in northeast Brazil, consists 
                         of a complex set of crustal blocks of different ages, origin and 
                         evolution, with final amalgamation during the late Neoproterozoic 
                         Brasiliano Orogeny. In the central part of the province, its 
                         Transversal sub-province is characterized by elongate NE-SW 
                         terranes largely affected by the Brasiliano metamorphic 
                         overprinting and by a suite of early Neoproterozoic metavolcanic 
                         and metaplutonic rocks, reflecting a distinct tectonic event 
                         (Cariris Velhos). Magnetotelluric (MT) data were collected at 64 
                         stations along four profiles across this central region of the 
                         province to assess its deep electrical resistivity structure. 
                         Dimensionality analysis shows that the subsurface is electrically 
                         dominated by 3D structure, and 3D inversions of the full impedance 
                         tensor and vertical magnetic transfer function (tipper) were 
                         carried out. Data fit is relatively good with an acceptable 
                         distribution of the misfit between the sites and the dominant 
                         features in the final model are north-dipping crustal conductors, 
                         which can be tentatively correlated between the different MT 
                         profiles and cross contrasting terranes at the surface of the 
                         province. Considering the geometry and distribution of the 
                         conductors, it is proposed that they might reflect remnants of a 
                         north-directed subduction zone with enhanced conductivity 
                         associated with graphitized biogenic material in metasedimentary 
                         rocks originally deposited in a restricted oceanic environment and 
                         subsequently metamorphosed and introduced into the deep crust by 
                         the subduction of the oceanic lithosphere. Constrained by isolated 
                         outcrops of early Neoproterozoic rocks with oceanic affinity, the 
                         proposed subduction event may have taken place during the Cariris 
                         Velhos Orogeny with the crustal remobilization by the Brasiliano 
                         Orogeny being restricted to the brittle upper crust. This 
                         interpretation gives support for an accretionary model to the 
                         Neoproterozoic geodynamic evolution of the Borborema Province.",
                  doi = "10.1016/j.precamres.2015.12.012",
                  url = "http://dx.doi.org/10.1016/j.precamres.2015.12.012",
                 issn = "0301-9268",
             language = "en",
           targetfile = "Padilha_deep.pdf",
        urlaccessdate = "27 abr. 2024"
}